Aboveground biomass is all the plant material
above the ground in a forest. That includes live
trees, dead trees, branches, leaves and shrubs.

The plant life on earth is nature's storehouse
of chemical resources and solar energy. This
natural wealth is potentially a significant
renewable energy resource. Estimating tree biomass
is an important way to measure the energy potential
of a forest. Biomass equations for individual trees
are used to predict forest production and its
relation to stand density, to compare biomass and
production for individual trees species, and to
estimate forest fuel potential.

To estimate the biomass found on Saltonstall
Ridge, we applied biomass equations from "Biomass
Equations for Sixty-Five North American Tree
Species" published in Forest Ecology and
Management (see below). The equations
estimating biomass were developed by relating
biomass to tree diameter at breast height (DBH) and
other tree characteristics. Individual tree species
often have more than one biomass equation due to
the fact that the biomass equations were produced
in several different geographical locations.
Consequently, we had to use biomass equations
developed at sites with different conditions than
at our own site.

In "Biomass Equations for Sixty-Five North
American Tree Species," the author suggests different
approaches that researchers can take to minimize sample
error:

find the geographically closest site

use several reported equations to estimate the range
of biomass

generate biomass data using various published
equations and fit a new equation to the generated
data.

For the purposes of our study, we selected equations from
the geographical regions closest to our sample area. In
every case, we used the equation for total above ground
biomass (AB). The majority of the biomass equations are in
the form m=aD
b, where m is the overdry weight
biomass of the tree (kg), D is the dbh (cm) and a and b are
parameters. The parameters a and b are different for every
species. These formulas give reasonable estimates of above
ground biomass based on tree species and dbh.